Die-casting machine



Dec. 2%, 1932. N. LESTER DIE CASTING MACHINE Filed Jan. 19, 1931 3 Sheets-Sheet l flrronmsrs DEC. 20, 1932; LESTER 1,891,894

DIE CASTING MACHINE Filed Jan. 19, 1931 5 Sheets-Sheet 2 /IYVEIY r012 7 W1 T/vEss Dec. 20, 1932. LESTER 1,891,894

DIE CASTING MACHINE Filed Jan. 19, 1931 5 Sheets-Sheet 5 nnn n nnnn! nnnl "ll/ll (III;

Hill!!! 8,- www/ \v frivsss Patented Dec. 20, 1932 UNITED STATES PATENT OFFICE NATHAN LISTER, OI CLEVELAND, OHIO, ASSIGNOR TO PRECISION CASTfiVGS COMPANY,

INC., 01' SYRACUSE, NEW YORK, A CORPORATION OF NEW YORK DIE-CASTING MACHINE Application filed January 19, 1931. Serial No. 509,746.

This invention relates to die-casting .ma-

chines in which a delivery pot operates in conjunction with a movable die section and wherein the delivery pot and movable die section are moved into and out of casting relation with a fixed die section by fluid pressure.

One of the objects of this invention is to provide a casting machine with an improved means for supplying molten metal to the die cavity.

Another object is to provide a novel and improved means for ejecting castings from the die. A further object is to provide an eflicacious means for operating and controllin the various moving partsof the machine.

ther objects and advantages relating to the particular form,-relation andoperation of the various parts of the device, will more fully appear from the following description, taken in connection with the accompanying drawings, in which Figure 1 is a front elevation, partly in section, of a die-casting machine embodying the various -features of this invention, the machine being illustrated in the inoperative or casting ejecting position.

igure 2 is an enlarged'longitudinal vertical sectional view taken on line 22, Figure 1, and illustrating the construction of a 7 suitable fluid control valve for this machine.

Figure 3 is a transverse vertical sectional view taken substantially in the plane of the line 33, Figure 4, with the machine illustrated in the'operative position ready to form a casting.

Figure-4 is a detail transversehorizontal sectional view taken on line 4-4, Figure 3.

Figure 5'is a transverse horizontal sectional view taken on line 55, Figure 1.

Figure 6 is an enlarged detail transverse vertical sectional view through the delivery pot taken in the plane of the line 66, Figure 4.

tional view of one of the swivel joints taken on line 77, Figure 5.

Figure-8 is a detail vertical sectional view taken on line 8-8, Figure 1. a

The apparatus, asillustrated in the drawthrough a suitable opening 14 provided Figure 7 is an enlarged longitudinal sec-' ings, consists of a base 1 substantially square in plan view, and having each corner thereof rovided with an upwardly extending hol ow boss 2 adapted to receive therein one end of a vertically disposed ie rod 3. The tie rods "-3 extend upwardly some distance above the base 1 and have secured to the upper ends thereof a fiXeddie-supporting plate 4. The plate 4 is substantially square in plan view similar to the base -1 and is provided at each corner thereof with an opening -5 adapted to receive a respective tie rod -3- therethrough.

The plate 4 is adj ustably secured to the tie rods -3 by means of nuts 6 screwthreaded on the upper ends of said rods and positioned one at the upper and lower sides of said plate, Positioned intermediate the base 1 and the fiized die-supporting plate 4- is a movable die-supporting plate This plate 7 is made similar in plan view to the base 1I and has each corner thereof provided with a hollow boss 8 for receiving a respectivetie rod 3- therethrough so that the plate 7' will be guided by said rods as it is moved vertically towards and away from the fixed die-supporting plate This vertical movement of the plate 7- is eflected, in this instance, by means of'fluid under pressure actuating a cylinder 9 which, in turn, is operably connected with the plate 7 through the medium of a toggle link mechanism-10. Within the cylinder 9- is positioned a piston '12 which is connected with one end of a piston rod -13 which extends downwardly in the lower head plate 15 for the cylin-, der 9 and has the lower end thereof secured to the base -1.

The rod 13- is adjustably secured to the base 1 to permit the proper positioning of the cylinder -9- respective'to the plate 7, and for this purpose, the lower endof the rod 13 is screw-threaded in the base 1 and may be permanently maintained at a predetermined position by means of a lock nut 16- screw-threaded on the rod 13- in contacting relation with the base 1.

The-cylinder 9- is also provided with a second head plate -17 similar to the plate 15- and which is positioned at the upper end of said cylinder. The cylinder 9 and the head plates 15- and 17 are secured together by bolts -18 or their equivalent, which pass through-suitable openings in the head plates +15- and 17- and are screwthreaded in the adjacent end of the cylinder wall. The head plate 17 is provided with a port +20- in communication with the interior of the cylinder 9. Said port is also connected by means of a conduit -21 to a suitable fluid control valve which will behereinafterinore fully described.

One side of the cylinder 9 is made to extend outwardly to form a substantially flat vertical surface '9' to which is secured by screws 22 a double-faced rack 23', the opposite vertical side edges of the rack 23 being provided with gear teeth which are in meshing engagement with respective segmental gears 24.

Each of the gears 24- are pivotally connected at 25 to an upwardly extending boss or arm 26- secured to or made integral with the upper face of the base -1-, the teeth of these gears -2 1 being made concentric with the pivots -25 so as to always remain in meshing engagement with the rack 23 throughout the entire roclc'ng movement of-said gears Pivotally connected to the upper outer edge of each of the gears 24 as at 27 is one end of a rock arm --28 which has the other end thereof pivotally connected at 29 to a link 30 which, in turn, is pivotally connecte'd at 31 to a downwardly extending lug 32- secured to or made integral with the lower face of the movable die-supporting plate 7.

A cross head -'34- is positioned intermediate the arms 28 and has the opposite vertical side wallssthereof provided-with outwardly extending arms 34', each of which is pivotally connected at 35 to a respective rock arm 28 intermediate the ends thereof. The cross head -34, in this instance, is provided with a recess 36- which extends upwardly from the lower edge thereof and is adapted to receive therein the upper portion of the cylinder 9- so as t6 permit the free operation of the cylinder 9 and to conserve space.

The conduit 21 secured to the cover plate 17 of the cylinder -9 extends outwardly from said head plate through a suitable elongated slot -37- provided in one face of the cross head 34 which permit-sthe free movement of the cylinder 9 in said recess 36, as will hereinafter be more fully described. 4

The lower head plate 15 of the cylinder --9 is also provided with a port 38 which is in communication with the interior of the cylinder and also connected by a conduit as 39- which has one end thereof extending through a suitable opening in the rack 23 and screw-threaded in the port -38 while the other end of said conduit is connected with the hereinbefore mentioned control valve 40.

It is now evident that any vertical movement ofthe cylinder 9- will cause a corfor receiving ejector pins 42, and for this reason, the die 41- will hereinafter be called the ejector die section. The ejector pins 42 extend downwardly from the die 41 into a suitable recess 43- formed in the upper face of the movable die-supporting plate 7 beneath the ejector die 41-.

The lower ends of the pins 42 are secured to a suitable ejector plate 44- positioned in the recess 43- and which, .in turn, is secured to a suitable ejector plunger 45- slidably mounted in an aperture provided in the plate 7 beneath the recess 43-. The ejector plunger 45 extends downwardly below. the plate 7- with the lower'end thereof adapted to contact with the upper end of the cross head 3 1 in such a manner that when the toggle mechanism 10. is in the extended position, the upper ends of the ejector pins 42will be in registration with the adjacent wall of the die cavity to form a smooth continuous surface of the die cavity. j

Also secured to the upper face of the movable die supporting plate -7 is a delivery pot 57-. The delivery pot 57 may be secured in, any suitable manner to the plate 7 as by screws --58, said pot being provided with a pressure chamber 59 which, in this instance, is a groove or slot formed in the upper face of the pressure pot 57 to extend longitudinally thereof. The pressure chamber 59-, in this instance, has the vertical longitudinal side walls thereof tapered outwardly for receiving a similarly constructed plunger 60.

The delivery pot 57 is so mounted on a the plate -7 that the inner end of the chamber 59 will be closed by theejector To the under face of the fixed die support-- ing plate is secured by any suitable means, as screws6l-, a die section 62 which, in this instance, is provided in its lower surface with a suitable gate or sprueforming passage 63 and, therefore, this section of the die will hereinafter be termed the sprue die section. The sprue-die section 62 is so constructed that one side thereof will extend outwardly over the delivery'pot 57 to form a closure for the pressure chamber 59 when the ejector die 41 is in casting relation with the sprue die 62 as illustrated in Figure 3.

The plunger 60 is formed to have a close sliding fit in the chamber '59 and between the lower wall of the chamber and a the lower face of the sprue die section -62-,

' plate or extension are screw-threaded stance, has the outer ower when the die sections 41 and 62 are in casting relation for the purpose of ejecting molten metal which may be contained in the chamber 59 from said chamber through the gate 63 into the die cavity. The longitudinal reciprocative movement of the plunger in the chamber 59 may be produced by any suitable means such as fluid as oil under pressure, operating upon a piston 65 mounted for longitudinal reciprocative movement in a cylinder 66 and which is connected with the plunger 60V by means of a piston rod -67-, a slide 68 and a connecting rod 69, all of which may be mounted in any suitable manner so as to move vertically with the do? livery pot -5 7- and, for this purpose, one side of the die supporting plate 7 is projected out\vardly7 to form a supporting The outer'end of tension 7 is provided with an upwardly extending vertically disposed flange 70 which has the outer vertical face thereofprovided with a recess 70- for receivingone end of the cylinder '66 and forming an end plate therefor.

Positioned adjacent the outer end of the h I cylinder 66 is a second cover plate 71 the cylinder 66 and plate 71 being securedtogether and to the plate 70- by means of a plurality of, in this instance six, screws or bolts 72 which pass through suitable openings in the end plate -71 and in-the plates 70-. The piston rod 67' extends outwardly through a suitable opening 73- provided in the end plate 70+ concentric with the cylinder 66 and is screw-threaded in the slide 68. The slide -68, in this inlongitudinal edges thereof provided with outwardly extending flanges 68 adapted to travel in a corresponding groove 7L formed in the inner faces of a longitudinal flanges 75 formed integral with or secured to the upper face of the extenthe supporting plate ex 41 der 66.

pair of upwardly extending spaced .sion 7" for guiding the slide 68- in The delivery pot 57 may be formed. with the chamber 59- adapted to contain a more or less molten metal depending upon the size of the die cavity which will, of course, necessitate the forming of different sizes of plungers 60 to conform to the size of the chamber 59 and, for this reason, the T- slot 76 formed in the slide -68- is of suflicient length to permit the necessary positioning of the rod -69 caused by the different sized plunger-s used, without the necessity of providing separate means for securing the rod- 69 to the slide 68.

It is evident that during the forcing of the metal from the chamber -59 into the die cavity that a considerable side thrust will be produced upon the die section 41 due to said die forming a closure for the inner end of the chamber 59, and for the purpose of maintaining the die 41 in contact with the inner end of the delivery pot 57 under all pressure conditions, a pair of stay bolts 78 are screw-threaded in an upwardly extending flange 79 formed at the opposite side of the plate 7 to thatat which the extension 7- is provided, said bolts being so constructed that the inner ends thereof will engage the adjacent face of the die section Each of the cover plates 70'and '71 for the cylinder 66 is provided with a respective inlet port 80 and 81 in communication with the interiorof the cylin- The inlet port -8 0- is connected by a suitable conduit 82 to the hereinefore mentioned control valve 40- while the port 81 is connected by a similar conduit 83- to said control valve.

It is evident that as the cylinder -9- is moved vertically for transmitting a similar movement to the die plate 7 to bring the ejector die section -41 and the delivery pot .57 into and out of casting relatlon with the .sprue die section 62 that some suitable means'must be employed in the conduits 21-, -39-, 8*2-. and -83 for permitting this movement, and for this purpose. each of said condults is provided with a sutlicient number of suitable swivel joints as 85 whch will permit the required relative movement of certain portions of respective conduits relative to the remaining portion thereof and, at the same time, prevent any leakage or escapement of the fluid used forproduc-ing these movements.

The hereinbefore mentioned control valve 40 may be of any suitable construction for controlling the fluid passing to the cylinders 9- and -66 for'producing the required movements of the respective units actuated thereby. In Figure 2 more par.- ticularly is shown a simple valve which may be utilized for this purpose and which consists of a body portion 86 substantially rectangular in cross section and having a longitudinal bore -.87- extending therethrough substantially midway between the upper and lower faces of the body.

The ends of the bore 87 are closed by suitable end plates 88 and -89 which are secured to the respective ends of the body 86 by screws 90. The valve 40 is also provided with an inlet port 91 which, in this instance, is located in the upper portion of the body 86- substantially midway'between the ends thereof and is connected by a suitable conduitas --92 to any convenient means for supplying fluid under pressure, such as a pressure tank or pump not shown.

The valve 40- is also provided with .a plurality of, in this instance four, control ports 93, two of'which are located at the left hand side of the inlet port -91 and two at the right hand side of said port. These control ports 93'are spaced substantially equal distances apart and from the inlet port 91 and are each connected with the piston chamber .97 of the valve by means of annular recesses 94 formed in the wall of the chamber 87.

The inlet port 91 is likewise provided with an annular recess 95 which also connects said port with the chamber 87. 40 The recesses 94--and -95 are constructed of such a width that the distance between the adjacent walls thereof will be substantially equal, thereby forming annular flanges -87' surrounding the chamber -87-, all 45 of which will be of substantially the same width.

A piston 96 is mounted for longitudinal reciprocative movement in the chamber 87. The major portion of the pis- 50 ton 96 is made substantially smaller in diameter than the chamber 87 and is provided near each end thereof with an outward ly extending annular flange 96'- which are of substantially the same diameter as the i chamber 87- and have'the same width as the flanges --87.'-,

The piston flanges -96'- are spaced apart a distance substantially equal to the distance between the outer wall of one of the outer positioned recesses '-94 and the opposite wall of the intake recess -95, as-clearly shown in Figure 2.

ach of the outer ends of the chamber 87, in this instance, is connected by respective ports -97' to a common outlet p i g chamber 98- which extends longitudinally through the body -86 below the chamber -87'. The outlet chamber -98- is connected by asuitable conduit 99 with the source of fluid supply for returning the fluid thereto.

Each of the conduits 21, 39, -82- and -83 is connected with a respective control port --93 in such a manner that the operationof the movable units of the diecasting machine may be progressively controlled by moving the piston 96 from one end of the chamber 87 to the other. This movement of the piston 96 may be effected by any suitable means such as a lever 100 which, in this instance, is pivotally mounted at 101 to a bracket 102- secured to or made integral with the body 86 of the valve 40, or as illustrated in this instance, may be made integral with the end plate -89 for said valve.

The lower end of the lever -100 extends below the pivot l0l and is made concen: trio with said pivot and provided with gear teeth 103 formed in the lower peripheral wall thereof for engaging a suitable rack member 104 which is slidably mounted in a bore 105 formed in an outwardly projecting flange 106 secured to or made integral with the bracket -102.

This rack -104 in turn is connected with the piston 96- by means of a piston rod 107 which has one end thereof secured to the piston 96-- and extends outwardly through a suitable opening -108 provided in the end plate -89 and has the outer end thereof adjustably secured to the rack 104-.

The piston -96 may be releasably maintained in any one of a plurality of, in this instance three, positions in -87 for maintaining the fluid pressure in the desired end of the cylinders -9' and -66, and for this purpose, the bracket 102- is provided with a slot 109 positioned above the pivot 101 and made concentric therewith for receiving a pawl -110 which is slidably mounted in a suitable groove 111- formed in the lever -100-, said pawl having a laterally extending arm adapted to travel in the slot -109 and in any one stance three, radial slots 109'.f0rmed in the upper surface of the slot 109.

The pawl --110- may be yieldingly maintained in engagement with the radial slots 109- by means of a rod --112- and 113, said rod having one end thereof connected with the pawl -110 and the outer end positioned in a suitable recess 114 formed in the outer end of the lever 100.

The spring '-113+ is positioned in the recess -114 between the lower or inner end of said recess and a suitable nut 115 the chamber of a plurality of, in this inv screw-threaded on the outer end of the rod 112, said nut 115 being so arranged as to normally extend above the outer end of the lever 100 so that the pawl -110 may be readily moved downwardly against the action of the spring 113- by av slight pressure upon the nut -115.

Operation Assuming now, that the control valve 40 is connected with a source of fluid supply adapted to supply fluid under very high pressure and that the piston 96- is positioned at the extreme right hand end of the chamber -87-, as illustrated in Figure 2, this will cause the lower end of the cylinder 9- to be connected through the conduit 3.9 and chamber 87 with the inlet port 9l of the valve 40-, which will position the cylinder -9 in its lowermost position,'and therefore cause the movable die-supporting plate 7 to be in its lowermost position, as illustrated in Figure 1.

The inner or rod end of the cylinder 6G will also be connected with a source of fluid pressure which will maintain the plunger 60 in its outermost position with the pressure chamber -59 in position to receive a charge of molten metal. The pressure chamber 59 may now be filled with molten metal after which the piston 96 may be moved inwardly toward the left hand end of the chamber 87- to bring the conduit 39 into communication with the outlet 97- and the conduit '2l into communication with the inlet port 91'--. This will permit the fluid, under pressure, to flow through the-port into the upper end of the cylinder 9-, which will cause said cylinder to move u wardly due to the piston 12- being fixed y supported by the base 1-.

The upward movement of the cylinder ,9- will. cause the rack 23- secured thereto to rock the gear segments 24- about their respective pivots 25 and thereby cause the toggle mechanism 10-- to assume the extended position and move the die-supporting plate 7 upwardly to bring the'ejector die section et1 and the pressure pot 57 into casting relation with the sprue die section 62. This upward movement of the plate 7- will, of course, carry the cylinder 66- upwardly and position the pressure chamber 59 with the inner end thereof in communication with the gate --63 of the sprue 'die section 62.

Now, by moving the piston -96- of the Valve to the extreme left hand position in the chamber 87., the inner end of the cylinder 66 will be cut ofi from the source of fluid supply and connected with the exhaust conduit, -99, while the outer end of said cylinder will be connected with the source of fluid supply. This will cause ment ofthe plunger into the die cavity.

It is evident that any excess metal remaining in the pressure pot after the die cavity has been filled, will be positioned at the forward or inner end of the pressure chamber -59 in contact with the sprue formed in the gate or passage 63-.

As the quantity of the excess metal in the pressure pot 59' will be comparativelysmall, the metal will very quickly solidify so that upon the plunger 60- being returned to the normal outer position by the proper manipulation of the piston 96, said excess material will remain in connection with the sprue.

As the piston 96 is moved towards the right hand end of the chamber 87' to its original position, the plunger 60- will first be returned to its normal outer position due to the inner or rod end of the cylinder 6G being connected with the source of fluid supply, and as the piston 96 continues the return movement, the lower end of the cylinder to move to its lowermost position which will cause the rack 23- to rotate the gears 24 and move the toggle mechanism to the folded position, which will cause the movable die supportin plate ,7 to return to its lowermost position, as illustrated in Figure 1.

It' is now evident thatas the cross head 34 is carried by the arms 28, that said cross head will travel a less distance than the die supporting plate -.--7 which-will cause the plate -7 to approach the upper end of the cross head 34"as'-the plate 7 approaches its lowermost position. This will cause the ejector plunger -45-- to be engaged by the cross head 34 and move it upwardly through the die supporting plate -7.

This upward movement of the ejector plunger 45 will, of course, cause a corresponding upward movement of the ejector pins 42 through the ejector die section 41 and thereby discharge the casting from the die section :41 after which the casting may be readily removed by the operspirit of this invention as set forth. in the appended claim.

I claim: A die-casting machine comprisin in combination a pair of die sections, a xed diesupporting plate forv one of the die sections, a movable die-supporting plate for the other die section, a delivery-pot secured to themovable die-supporting plate for movement therewith, a plunger mounted for reciprocative movementin said pot, actuating means 10 connected with the plun er for operating said plunger and secure to the movable plate for movement therewith, and separate operating means for moving the movable plate and associated-parts towards and from the fixed plate.

- In Witness whereof I have hereunto set my hand this 18th day of December, 1930.

NATHAN LESTER. 

